Randi and Leah are studying together for an exam. Let X represent the number of hours Randi spends studying nightly, and let Y represent the number of hours Leah spends studying nightly. The mean of X is 4.5 hours with a standard deviation of 1.1 hours, and the mean of Y is 3.7 hours with a standard deviation of 1.8 hours. Assuming these are independent random variables, which answer choice correctly calculates and interprets the standard deviation of the sum, S = X + Y? Mu Subscript s Baseline = 0.7; Randi and Leah can expect the total number of hours spent studying to vary by approximately 0.7 hours from the mean.
Mu Subscript s Baseline = 1.7; Randi and Leah can expect the total number of hours spent studying to vary by approximately 1.7 hours from the mean.
Mu Subscript s Baseline = 2.1; Randi and Leah can expect the total number of hours spent studying to vary by approximately 2.1 hours from the mean.
Mu Subscript s Baseline = 2.9; Randi and Leah can expect the total number of hours spent studying to vary by approximately 2.9 hours from the mean.